Combined spring and friction shock absorbing mechanism



G. E. DATH April 9, 1946. r 2,398,083

' COMBINED SPRING AND FRICTION SHOCK ABSORBING MECHANISM Filed Aug. 25, 1944 M w I Patented Apr. 9, 1946 UNITED STATES PATENT OFFICE COMBINED SPRING AND FRICTION SHOCK ABSORBING MECHANISM George E. Dath, Mokena, Ill., assignor to W. H.

Miner, Inc., Chicago, 111., a corporation of Delaware Application August 25, 1944, Serial No. 551,206

'7 Claims.

One object of the invention is to provide a 5 yoke and the parts therewithin for movement combined spring and friction shock absorbing lengthwise of the car. On the inner sides, the mechanism h v n m y pring action followed draft sills Ill-l are provided with guides l-l 5 y m in prin an frictional r si n e d of well-known form to center the draft gear. in t e att p Of the p ess o The yoke I3 contains the usual front and rear wherein snubbing means is provided for dampenl0 follower members d n and my improved ing the spring action to reduce oscillations to a combined spring and friction shock absorbing mimmum. mechanism.

A more specific object of the invention is to My improved combined pring and frictign p v de a mechanism s et forth in the precedshock absorbing mechanism comprises broadly a epag r ah g mpfifgns l l ggsp i g i t- 15 mafin spring resistance A; a friction casing B;

1 1 s 0 0 1S a riction post C integral with the casing; a resisted by the main spring resistance; a fric- Wedge block three fri ti Shoes tion clutch receiving the actuating force and an inner spring F within the casing a pair having sliding frictional engagement with the inf fri tion elements and a spring H coopgfif lgid ggjegq erg fctafingiltzh vlgfifi re gl a ig fi crating with the friction elements to press the 0 same against the post C. the casi g; and means for snubbins t action The friction casing B is in the form of a cylat its rear end b a transverse ve tical all l8.

and friction blocks yieldingly pressed against the At the open from: end, the casing is pvgovided post to frictionally oppose movement of the post with an outstanding annular flange '9 which and casing, wherein the friction casing is moved functions as a spring follower member The by the gripping action of the clutch to compress casing B has the walls at the front end portion the main Spring resistance during the major thereof inwardly thichened as indicated at 20 tion of the compression stroke of the mechanism, Said th'ickened portion of casing forming zfig g zgg fgggg fi gfig figg ifif gzgg g the friction shell proper of the mechanism. The relative m gement of the clutch and casin i friction shell portion of the casing B is provided mg the reljnainder of compression Strike to with three interior, longitudinally extending fricprovide high frictional resistance to take care non surfaces gf'FFi. i transverse of the heavier shocks to which the mechanism is Press Sec r m ages converge Subjected inwardly of the casing. The friction post 0 is in the form of a heavy, fiat plate of rectangular gggs gggg g; tgz 22x52 3;g g ggg ggzgg outline, which is formed integral with the casing after following 40 B and extends lengthwise of the mechanism, pro- In the drawing forming a part of this specijecting rearwarfily the Wan P the F flcation, Figure 1 is a horizontal, longitudinal g on .oppljslte 810165 h post 0 Provlded sectional View through a portion of the under with longitudinally extending, flat friction surframe structure of a railway car,1llustrating my faces 2 improvements in connection therewith. Figure 4 h wedge? 15 m the form M q block 2 is a front end elevational view of the combined havmg vertlca'l front end face Whlch bears spring and friction shock absorbing mechanism f= 0 the fl follower of the draft illustrated in Figure 1. Figures 3 and 4 are P h Inner f the Wedge m D transverse, vertical sectional views, correspond- 1S Provlded Wlth r e inwardly converging flat ing respectively to the lines 3-3 and 4-4 of Wedge faces arranged symmetrically Figure about the central longitudinal axis of the mech- In said drawing Iii-l0 indicate channel- 'anism, The wedge block D is further provided shaped draft sills of a railway car underframe with three radial lugs 35-25-25 at the inner to the inner sides of which are secured the usual end thereof, which proJect outwardly and are front and rear stop lugs l'l-H and H-l I. The 66 adapted to engage in back of three circumfereninner end of the coupler shank is indicated by 12 and a yoke i 3 of well-known form is secured to the shank. A saddle plate l4 secured to the underneath side of the draft sills supports the tially spaced, inturned lugs 262628 at the front end of the casing B.

The friction shoes E are three in number and surround the wedge block D. Each shoe has a V-shaped outer friction surface 21, which engages with the corresponding V-shaped friction surface 2| of the casing B. On the inner side, each shoe has a flat wedge face 28, which engages the corresponding wedge face 24 of the wedge block D,

The spring resistance F is in the form of a helical coil disposed within the casing B and bears at its front end on the inner ends of the three shoes EE-E and at its rear end on the transverse end wall iii of the casing. The spring F is preferably under initial compression, thus pressing the shoes against the wedge block which is held against outward movement of the casing by shouldered engagement with the lugs 26-2 6- 26.

The two friction elements GG are in the form of elongated, platelike members, each having a flat, longitudinally extending friction surface 29 on the inner side thereof cooperating with the corresponding friction surface 22 of the post C. Each element G is laterally enlarged or thickened, at the front and rear ends, as indicated at 3030, The thickened portion at at the rear end of each element G is provided with a laterally projecting end flange 3!, which is of arc-shaped form, The

two elements C--G embrace the post C at opposite sides and the two flanges 31-3! of said elements together form, in effect, a two-part circular follower flange corresponding in outside diameter to the annular flange I9 of the casing B, The outer sides of the shoes are transversely curved, thus presenting semi-cylindrical, outer surfaces 32S2 which are of the same radius and concentric. The opposite edge faces of the post are also curved transversely, as indicated at 3333. The faces 33-33 are concentric but of shorter radius than the surfaces 32-32 of the elements G-G. The surfaces 33-33 of the post are thus slightly inset with respect to the surfaces 32-32 of the elements G--G. Each element G is further provided with wedge faces 3535 at onposite ends thereof, the wedge faces 3535 facing inwardly and being formed on the enlargements SIP-3D. Each wedge face is preferably of conical contour.

The spring resistance H is in the form of a light helical coil which surrounds the elements G-G and has the coils at opposite ends thereof in wedging engagement, respectively, with the wedge faces 353 5. The spring resistance H is under a predetermined constant compression and wedges the elements (3-6: against the post C.

The main spring resistance A is in the form of a relatively heavy, helical coil, which surrounds the casing B and the friction elements G-G, and bears at its front end on the flange IQ of the casing B and at its rear end on the flanges 3I-3l of the friction elements GG, The post C has its rear end normally spaced from the follower l1 and is adapted to engage said follower to limit inward movement of the casing B to less than the full compression stroke of the mechanism. When the mechanism is fully compressed, the post C in conjunction with the casing B acts as a solid column to transmit the actuating force from the from follower IE to the rear follower l1 and prevents undue compression of the spring A.

The operation of my improved combined spring and friction shock absorbing mechanism is as follows: When the coupler is pulled forwardly in draft or moved inwardl in buff, the followers l6 and l! are moved inwardly toward each other, thereby compressing the shock absorbing mechanism. During compression of the mechanism, the wedge block D is forced inwardly, wedging the shoes EEE apart and pressing the same tightly against the friction surfaces of the casing B. Due to the frictional resistance produced by this wedging action, the clutch, comprising the wedge and friction shoes, tightly grips the casing and compels the same to move inwardly in unison with the wedge block D. As the casing B is moved inwardly, the main spring resistance A is compressed between the follower flanges of the casing and the friction elements GG. During this action, the friction post slides inwardly or rearwardly between the friction elements GG, which are forced against the post by the spring H, thereby effectin a snubbing action of the main spring resistance A. The described action continues until the outer end of the post C engages the rear follower l1, whereupon movement of the post and the casing B is arrested, compelling inward movement of the wedge D with respect to the casing during the remainder of the compression stroke. During inward movement of the wedge D with respect to the casing B, high frictional resistance is created between the friction surfaces of the casing and the shoes E--E--E. Compression of the mechanism is finally limited by engagement of the front follower IS with the front end of the casing B. During release of the mechanism, the main spring resistance A returns the casing to the normal position shown in Figure l and the spring F returns the friction shoes and Wedge block to their normal positions, outward movement of the wedge block being limited by engagement of the lugs 25 thereof with the lugs 26 of the casing,

As will be evident, the action of the main spring resistance A is effectively snubbed during both compression and release of the mechanism by the spring pressed friction elements G-G which cooperate with the post C, which is integral with the casing B.

I have herein shown and described what I now consider the preferred manner of carrying out my invention, but the same is merely illustrative and I contemplate all changes and modifications that come within the scope of the claims appended hereto,

I claim:

1. In a combined. spring and friction shock absorbing mechanism, the combination with a friction casing open at one end and closed at the other end; of a friction post projecting lengthwise from said closed end of the casing; friction elements embracing said post and with which the post has sliding frictional engagemerit; a spring surrounding said elements and pressing the same against the post, said casing and elements being lengthwise movable toward and away from each other; a main spring resistance yieldingly opposing relative lengthwise approach of the casing and elements; a friction clutch slidingly teiescoped within the open end of the casing; a spring within the casing yieldingly opposing inward movement of the clutch; and. means for limiting inward movement of the post and casing to less than the full compression stroke of the mechanism.

2. In a combined spring and friction shock absorbing mechanism, the combination with a friction casing open at one end and closed at the other end; of a laterally outwardly projecting flange at said open end of the casing; a friction post projecting lengthwise from said closed end of the casing; friction elements embracing said post and with which the post has sliding frictional engagement; laterally outwardly projecting follower flanges at the outer ends of said elements; means yieldingly forcing said elements against the post, said casing and elements being lengthwise movable toward and away from each other; a main spring resistance interposed between the flanges of the casing and elements, yieldingly opposing relative lengthwise approach of the casing and elements; a friction clutch slidingly telescoped within the open end of the casing; a spring within the casing yieldingly opposing inward movement of the clutch; and means limiting inward movement of the post and casing to less than the full compression stroke of the mechanism.

3. In a combined spring and friction shock absorbing mechanism, the combination with a main follower; of a second main follower, said followers being movable toward and away from each other; a lengthwise movable friction casing open at one end and closed at the other end; a laterally outwardly projecting flange at said open end of the casing; a friction post fixed to the casing and projecting lengthwise from the closed end of said casing, said post being movable in unison with the casing and having its movement limited to less than the full compression stroke of the mechanism by engagement with said first named follower; friction elements embracing said post and with which the post has sliding frictional engagement; laterally outwardly projecting follower flanges at the outer ends of said elements bearing on said first named follower; means yieldingly forcing said elements against the post, said casing and elements being lengthwise movable toward and away from each other; a main spring resistance interposed between the fianges of the casing and elements, yieldingly opposing relative lengthwise approach of the casing and said elements; a friction clutch slidingly telescoped within the open end of the casing, said clutch including a wedge pressure transmitting block projecting outwardly of the casing and bearing on said second named follower; and a spring within the casing yieldingly opposing inward movement of the clutch.

4. In a combined spring and friction shock absorbing mechanism, the combination with a friction casing; of a friction post projecting lengthwise from the casing; friction elements embracing said post and with which the post has sliding frictional engagement, said casing and elements being lengthwise movable toward and away from each other; a main spring resistance yieldingly opposing relative lengthwise approach of the casing and elements; a friction clutch slidingly telescoped within the casing in frictional contact with the interior walls of the latter; a spring within the casing yieldingly opposing inward movement of the clutch; a spring surrounding said elements and having wedging engagement therewith to force the same against the post; and means for limiting inward movement of the post and casing to less than the full compression stroke of the mechanism.

5. In a combined spring and friction shock absorbing mechanism, the combination with a friction casing open at one end and closed at the other end; of a friction post projecting lengthwise from said closed end of the casing; friction elements embracing said post and with which the post has sliding frictional engagement; fixed wedge faces at opposite ends of said elements; a spring surrounding said elements and having direct wedging engagement with the wedge faces thereof for pressing said elements against the.

post, said casing and elements being lengthwise movable toward and away from each other; a main spring resistance yieldingly opposing relative lengthwise approach of the casing and. elements; a friction clutch slidingly telescoped within the open end of the casing; a spring within the casing yieldingly opposing inward movement of the clutch; and means for limiting inward movement of the post and casing to less than the full compression stroke of the mechanism.

6. In a combined spring and friction shock absorbing mechanism, the combination with a friction casing open at one end and closed at the other end; of a laterally outwardly projecting flange at said open end of the casing; a friction post projecting lengthwise from said closed end of the casing; friction elements embracing said post and with which the post has sliding frictional engagement; laterally outwardly projecting follower flanges at the outer ends of said elements; inwardly facing wedge faces at opposite ends of said elements; a helical spring surrounding said elements and bearing at opposite ends on the wedge faces at opposite ends of said elements for forcing said elements against the post, said casing and elements being lengthwise movable toward and away from each other; a main spring resistance interposed between the flanges of the casing and elements yieldingly opposing relative lengthwise approach of the casing and elements; a friction clutch slidingly telescoped within the open end of the casing; a spring within the casing yieldingly opposing inward movement of the clutch; and means limiting inward movement of the post and casing to less than the full compression stroke of the mechanism.

'7. In a combined spring and friction shock absorbing mechanism, the combination with a friction casing open at one end and closed at the other end; of a laterally outwardly projecting flange at said open end of the casing a friction post projecting lengthwise from said closed end of the casing; friction elements embracing said post and with which the post has sliding frictional engagement; laterally outwardly projecting follower flanges at the outer ends of said elements; a spring under constant compression yieldingly wedging said elements against the post, said casing and elements being lengthwise movable toward and away from each other; a main spring resistance interposed between the flanges of the casing and elements yieldingly opposing relative lengthwise approach of the casing and elements; a friction clutch slidingly telescoped within the open end of the casing; a spring within the casing yieldingly opposing inward movement of the clutch; and means limiting inward movement of the post and casing to less than the full compression stroke of the mechanism.

GEORGE E. DATH. 

